'People need to feel that they have been heard, even when you can't give them what they are asking for or can't be of particular help,' Halvorson writes. One simple way to show you're paying attention is to make eye contact and hold it.

Halvorson says that making eye contact is also an effective way to convey competence, and studies have shown that those who do so are consistently judged as more intelligent.

Expressing you understand someone's experience and hope the best for them produces tangible increases in trust. But if all you do is stand there when someone confesses their woes, you're not coming off as very likeable.

Being cocky

People often confuse competence with confidence, Halvorson says. While you can never have too much competence, there is a healthy -- and unhealthy -- dose of confidence to be aware of.

The dangers of overconfidence include being underprepared, setting unrealistic goals, biting off more than you can chew, and generally making bad choices, Halvorson explains. And all this leads to being the least-popular guy in the room.

Instead, convey a realistic sense of confidence that shows modesty. You'll be less likely to threaten people's self esteem, and your mistakes won't elicit nearly as many cheers when you make them.

Slouching

Sitting up straight has been found to lead to greater perceptions of competence, Halvorson says, whereas slouching can cause others to consider you less confident, low energy, and disinterested in what they have to say.

Not accepting a compliment

Accepting a compliment can be tricky because you don't want to seem egotistical.

But you also don't want to mumble a, 'Thanks, you too,' because that makes you seem self-conscious and socially inept.

So instead of giving phrases like, 'You look 10 times better than me' or 'It was all thanks to you,' Quora user Julian Reisinger suggests accepting the compliment with confidence by using phrases like 'Thanks! Hearing that feels really good' or 'Thank you! What an amazing experience.'

Step one requires dropping what you're doing and paying attention. Next, 'paraphrase what you've heard and ask clarifying questions,' he suggests. Evaluating means steering clear of quick judgment and jumping to conclusions: 'Make sure you have all the pertinent information before forming or expressing an opinion.' Finally, 'give feedback to let the speaker know that you heard them,' he writes.